Metallurgical process.



' A. G. BETTS. METALLURGICAL PROCESS.

APPLIOATION FILED FOV.80,1906.

938,634. Phtented Nov. 2, 1909,

.wimesses INVENT'EIR all whom it may concern:

Be it known that I, .ANSON GARDNER arm, a citizen of the United States, residg at Troy, in the county of Rensselaer and ate of New York, have invented certain w and useful Improvements in Metal rgical Processes, of which the following is specification accompanied by a drawing. The single figure of the drawing shows apratus which I may use in carrying out my vention.

uminum, and in its preferred form to e metallurgy of iron. The principal object of the invention is n prepare pure aluminum cheaply from mmon raw materials, and in its preferred rm it is also an object of the invention to I. eaply prepare metals, especially iron, from eir sulfids. J o Other objects will appear in connection ith the following description of my method.

um ore by any suitable means in presnce of a comparatively easily reduced and latively not very volatile 'metal, or comound of such metal, producing thereby an lloy of aluminum and such other metal. uminum has a considerable combining ower with iron and with copper, for' ineadily reduced' presence of these metals, If such metals are present in the furnace harge as ores, they are so much more ready reduced than aluminum that their partial eduction at least takes place before any so that in any event he reduction of aluminum takes place in he presence of such other metal.

There are certain well-known electrical u ethods for making ferro-aluminum and alun um bronze by the reduction of alumina in I resence of iron and copper respectively, and ethods may be used in carrying out his invention,but I regardthereductioninthe d better adapted for a large production f aluminum. Y

Iron ore and aluminum ore, e. g., bauxite or kaolin, are charged with fuel in a blast furnace similar to an iron blast furnace, differing from an iron blast furnace however in action, in that a higher temperature is used in the smelting section of the furnace. The higher temperature may be produced'by using a more highly heated blast, but espe- Speeiflcation of Letters Patent. Application fled November 80,1906. Serial No. 345,774.

This process relates to the metallurgy of,

To carry out my invention I reduce alu- .ollowing manner as being more economical UNITED STATES PATENT! OFFICE.

Anson emmmn IBETTS, or TROY, nnw'roax.

mnrnnmmercnn rnoonss.

Patented Nov. '2, 1909.

cially well by blowing the furnace with air from which some of the nitrogen has been removed such a gaseous mixture may be produced by liquefaction and fractionation of air. a

In an iron furnace little or no aluminum is reduced with the iron, but a fair amount of silicon is formed. In smelting for ironaluminum alloys practicallyall the silicon present is reduced, and as silica is always a constituent of both iron and aluminum I ores, the product is not ferro-aluminum, but iron-aluminum-silicon. The most readily oxidized, sulfurized, chloridized etc., metal of the iron aluminum silicon, aluminum bronze, etc., being aluminum, the aluminum may be removed therefrom as pure aluminum compound by treatment with suitable oxidizing, sulfurizing and chloridizing rea nts. Thus treatment of iron-aluminums1 'con with silica at high temperatures gives a slag of pure alumina and ferro-silicon;

Fasim, 3Si0, r si 2A1, O,

or treatment of'iron-aluminum-silicon with iron ore gives, at hi h temperatures, pure fused alumina and erro-silicon, provided the iron ore is free from lime, magnesia, etc., otherwise the lime, magnesia, etc., will contaminate the alumina. The alumina produced may be utilized in the production of pure aluminum by the well-known methods. prefer however to treat the aluminum alloy with a sulfurizing a cut, especially with a metallic sulfid-as su d of iron, nickel, copper, etc., thereby producing aluminum sul fid which I .electrolyze for metallic aluminum, while the metal of the sulfid is re duced.

- The sense in which I use the term metal or viron in the claims, as being part of the furnace charge smelted to aluminum alloy, is thatthe metal, or specifically iron, may. be present either in the combined or elemental state. Theresult is substantially the same, as the metal, or iron, referred to, bein more reducible than aluminum, is reduced rst.

' 'The aluminum sulfid is more readily and cheaply reduced -to ;alumimim than the oxid is, and furthermore certain-metallic sulfids occur as ores or intermediate'smelting prod-- nets and are relatively much cheaper than the contained metal. and sulfur, both of which I am able to save by this rocedure.

I especially prefer the use iron sulfid,

beeause'it can be easily procured in large or carbon monoxid quantities, and so far no economical process has been devised, as-far as I am aware, to recover both the Iron and ulfur thereof.

The reaction between aluminum alloys and iron sulfid is approximately v 2A1+3FeS= A1 S +3Fe the preparation of silicon bronze reactin on an alloy of copper, aluminum and silicon resulting from thereduction o'f kaolin in presence of copper, with copper sulfid Numerous other alloys containing iron, nickel or cobalt, and copper may be made? and mixed sulfids may be used also in place of the simple sulfids, for example a mixture of iron and nickel sul- Q preparation of nickel-iron alloys, and the use of a mixture of nickel and copper sulfids in the manufacture of alloys containing copper and nickel, as German silver. Q The sulfids shouldbe brought together with aluminum, with both e fused condition, and I this may conveniently be done without its being necessa to especially fuse the alloy and sulfid, as b o in analogous ways,

fids in the the alloys containing sulfid and alloy in t th are produced as a result of smelting operations, together for reaction from the respective smelting furnaces.

Sulfid of iron occurs in nature in quantity in a fairly pure condition 'as yrrhotite and pyrite, but even in this case prefer to run the sulfid through a furnace with suitable additions to flux off the gan e, for the double purpose of gettin rido the gangue and for heating the su d.

When pyrite 1s smelte'd, I contemplate being able to increase the ield of sulfid by adding iron oxid to" the c arge to carry out these reactions:

- that is to say, the reaction is the de ipyrites by heat into fercomposition of the ions sulfid and sul The liberated sulfur acting on iron oxid in presence of. carbon produces a further quan tity of iron sulfid. I Y

- Inasmuch as. any iron, copper and nickel sulfids which are not decomposed byalumi; num, and remaining in the aluminum suljfid produced, would either'necessitate a speurification ofthe aluminum sulfid cial there rom before electrolyzinfi the aluminum sulfid for aluminum and s fur, or would cause the production of aluminum contamiiron, I mention the preparation steel by reacting on.

tainin treate with excess of iron sulfid, forming a sulfid, which matte is then and may be brought directly after tapping ture of iron and aluminum sulfids for exa m' .spout fi into suitable receptacles or electrol ic furnaces not shown. The crucible 1s I alloycontauu' 'ng considerabl less aluminum than it did origin take part in the next cg'cle ofoperations, the alloy containing alnminuni,

-metal by suitable met ceases 5 nated with respectively iron cofpper or nickel, vit is better to use an excess 0 aluminum in car 'ng out the reaction, so that the end pro d iicts of the reaction are aluminum sulfid substantially free from the sulfids of more ,7 readily reducible metals, and an alloystill containing some aluminum, which aluminum may be readily removed by oxidizing agents if desired. I y To insure the reafction'taking place to be 7 as complete as possible it is preferred to carry out the reaction in two stages. The alloy is first treated with an insufiicient quantity of iron sulfid, etc., to react with the aluminum present resulting in practically 8 pure aluminum sulfid. The alloy stillconconsiderable aluminum is then matte containing bothairon and aluminum used aloneor 81 together with fresh iron sulfid in the next 7 treatment of aluminum alloy. This is illus-1 trated in connection with-the accompan ing drawing in which I have shown a crucib e in which I may carry out my rocess. 9( The crucible consists 0 an iron shell" 1, lined with suitable refractory material 2. The shell is su ported on trunnions one of which 3 is indicated by dotted lines. The crucible can be tilted either wa bymeans of a gear 4, and spur 5 driven mm a suitable source of powernot'shown; The crucible has a s ut6 for fused sulfid and a spout 7for metal 1 A cycle of operations is as follows. The crucible contains to begin with a fused mixple from a previous operation. Fused ironaluminum-s'llicon is run in, when a-reaction takes lace, a large part of the aluminum of the al oy becomlng aluminum sulfid while 7 iron is. reduced from -the matte. The fused aluminumsuIfid is then poured off by tilting the crucible so that -it mayrun' out of the t en tilted backjto the originalrfiosition and fused; ferrous sulfid added. e products are fused aluminum-iron sulfid, and iron '11:;

I ally. T e alloy, ferrosilicon, isthen poured out .at the spout 6 by tilting the crucible the other way, leaving the fused sulfid mixture in the cruc1ble,f to "1' (1 used toreact with 1 c e ac pper or "other valuable metals, contemplate removing" the copper etc.,, as bottoms; or hods, before v In case the-iron the iron sulfid and alloy together. w' -p; I n 'carrying'out the reaction between aluminum-containin'galloy' to produce: ,llf minum compound practically. free thefaluminum-containing metals more readil reduced, the use of suitable fluxes for t e aluminum compound formed is ermissible, for instance cryolite consists in reducing aluminum oxid in presence of other suitable less-reactive metal, producing thereby an alloy of aluminum with a less-reactive metal, reacting on the alloy with a suitable material capable of producing therewith an aluminum. compound practically free from compounds of more readily-reducible metals than alumimum, and reducing aluminum from said aluminum compound.

- 2. The process of making aluminum which consists in reducing aluminum oxid in presence of other suitable less reactive metal, producing thereby an alloy of aluminum with a less-reactive metal, reacting on the alloy with a suitable metallic compound capable of reacting therewith to produce an aluminum compound practically free from compounds of less reactive metals, and reducin aluminum from saidaluminum com- 3, The process ofma'king aluminum which consists in reducing aluminum ore in presence of a suitable heavy metal, producing a heavy metal-aluminum alloy, reacting on the alloy with a metallic sulfid capable of -reacting with aluminum, thereby producing aluminum sulfid, and reducing aluminum from the said aluminum sulfid. I

4. The process of making aluminum which consists in reducing aluminum oxid in presence of a suitable eavy metal, producing a heavy metal-aluminum alloy, reacting on the alloy with iron sulfid, thereby producing aluminum sulfid, and reducing aluminum from the said aluminum sulfid.

5. The process of producing aluminum which consists-in smelting ore or earthy material containing iron and aluminum, producing thereby an alloy containing iron and aluminum, treatin the fused alloy with fused iron sulfid, t ereby producing aluminum sulfid, and reducing aluminum from said sulfid. I

6. The process of making aluminum which consists in reducing aluminum ore in presence of iron to an alloy containing iron and aluminum, reacting on the alloy with iron sulfid, thereby reducing iron and making aluminum sulfid, and decomposing the aluminum'sulfid electrolytically into aluminum and, sulfur.

7 The process of making aluminum which consists in reducing aluminum ore or oxid in the presence of a more readily reducible metal to an alloy of aluminum and such metal, treating said sulfid with said alloy, thereby recovering metal from said sulfid, and producing aluminum sulfid, and decomposing said sulfid electrolytically into aluminum and sulfur.

In testimony whereof I'have signed my name to this specification this 27th day of November, 1906, in the presence of two subscribing witnesses.

ANSON GARDNER BETTS.

Witnesses: a

' BENJAMIN STARBUCK,

RALPH H. SHERRY. 

